Latest theme for WordPress called TwentyThirteen is nice, but still doesn’t have Last Modified date in post meta. “Last Modified” date is required by Google to get an enhanced listing in search results. This requirements can be tested in Structured Data Testing Tool. So each site post must have 2 classes named date updated in the code and to show a date. Previously many people just added class updated to a regular date in a template loop code. This is the simplest solution, but doesn’t show the real update date. This time I just wanted to implement this from functions.php of my child theme and to have a real date of update. Even hidden with CSS it can provide a valuable hint sometimes.